“I think some journalists are enemy of the relevant and enemy of the news you can use,” Conway told CBS’ “Face The Nation.”
Pace Enguroo, it looks like Ms Miller, Yahoo, and/or the Huffington Post didn't mangle the quote. The official transcript of the program reads:
MARGARET BRENNAN: And you don't believe journalists--
KELLYANNE CONWAY: Sorry if I can't get--
MARGARET BRENNAN: --are the enemy of the people?
KELLYANNE CONWAY: I don't believe journalists are the enemy of the people. I think some journalists are enemy of the relevant--
MARGARET BRENNAN: Thank you.
KELLYANNE CONWAY: --and enemy of the news you can use. And I think that most of- most of the sins are sins of omission not commission- meaning--
MARGARET BRENNAN: Right.
1) “Enemy” is countable and should have an article in front of it. The transcript might have missed it, or Ms Conway might have been trying to talk quickly over the host's interruptions and left it out by accident.
2) It is common in English to omit “that” when its presence is easily understood by native speakers. In this case, the full form of the expression would be “the enemy of the news that you can use,” with the restrictive clause modifying the nearest noun. It just means useful news but gets said this way because of the pleasant rhythm and rhyme of the expression.
3) As Trom explained, rhetorical English can treat an adjective as a noun to describe the class of people or things which share that attribute. “The poor” are all poor people taken together, “the dead” are all dead people taken together, and “the relevant” here means all relevant news taken together.
The upshot is that Ms Conway is trying to affirm Mr Trump's main point (in his case mostly motivated by instinctive malice towards anyone saying unflattering things about him) by
leaving the indefensible ground his hyperbole established (America traditionally sees the free press as a bulwark of liberty rather than an enemy of the people, which is itself a phrase usually associated with Soviet totalitarianism); and
expressing a truism that at least some members of the press focus on sensationalism for the sake of ratings and advertising revenue, rather than careful consideration of facts for the sake of an informed public.
Supporters of Mr Trump will take away that she is supporting him; Mr Trump ideally will take away a better way to express his animosity without sounding like he's annoyed to be running a democracy with a free press; and opponents will be annoyed that she's moving the goalposts but can't really argue with the truth of what she herself has just said.